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MountRoyaleVenturesCashMineHydrology AddanBrown <br />1. INTRODUCTION <br />Mount Royale Ventures, LLC ("MRV") has submitted Amendment No. 2 for Permit M-1983-141 to the <br />Division of Minerals and Geology of the Colorado Department of Natural Resources (now known as the <br />Division of Reclamation, Mining, and Safety ["DRMS"]) on February 20 and 21, 2006. The review of <br />the submission by DRMS on February 22, 2006 raised a number of information requests related to <br />groundwater hydrology and geochemistry. This report provides the requested information, in the form of <br />responses to the questions raised by the Division. <br />2. GROUNDWATER GRADIENT <br />2.1 DRMS Request <br />63.3 EXHIBIT C - Mining Plan, Section S: Describe the groundwater gradient within the Cash Mine <br />and in the surrounding area. <br />It is the Division's position that discussion and methods for determination of the groundwater gradient <br />within the Cash Mine and surrounding area will need to be incorporated into the comprehensive <br />groundwater sampling and analysis plan, specified in Item 9 below. <br />2.2 MRV Response <br />The groundwater gradient within the Cash Mine can be described within the context of the groundwater <br />flow system of the area around the mine. The flow system has been investigated by evaluation of known <br />water levels in groundwater wells, hydraulic conductivity values derived from evaluation of the inflow to <br />the Cash Mine, and topographical information at the site. <br />2.2.1 Hydraulic conductivity based on infiltration <br />The groundwater level has been measured in four wells located towards the crest of the hill (Plate 1), and <br />found to be approximately 30 to 60 feet below ground surface in all four wells. This indicates that the <br />rockmass comprising the Gold Hill ridge is saturated close to the ground surface. This can only occur if <br />the permeability of the rockmass is sufficiently low to be unable to remove the infiltration from <br />precipitation from the mountain. The precipitation at Gold Hill is 19.5 inches per year, and the <br />infiltration to groundwater at this elevation would be expected to be in the order of 10% of this total, or <br />2 inches per year. This is equivalent to 0.1 gallons per minute per acre of area. The hill slope is <br />approximately 26%, and the rock that participates in flow down the hillside is estimated to be 3,500 feet <br />deep (equal to the distance from the ridge to the valley). <br />This data can be used to estimate the hydraulic conductivity of the 3,500 feet of rockmass from the ridge <br />to the valley below, using Darcy's Law for a one foot wide slice of the mountainside: <br />Q=KIA <br />K=Q/(IA) <br />where: Q = average flow down the hillside (2 in/yr/12 in/ft*3500 ft* 1 foot*0.5 = 292 cubic feet/year) <br />K = hydraulic conductivity <br />1 <br />1601A-20060911